Can I use GD instead of GD2?

No, I misunderstood.

The webhost support GD2.

Here is PHP information I get from phpBB

gd
GD Support enabled
GD Version bundled (2.0.28 compatible)
GIF Read Support enabled
GIF Create Support enabled
JPG Support enabled
PNG Support enabled
WBMP Support enabled
XBM Support enabled

But why I can't generate thumnails of the photos?

Configure Command './configure' '--enable-memory-limit' '--disable-debug' '--with-regex=php' '--disable-rpath' '--disable-static' '--with-pic' '--with-layout=GNU' '--with-pear=/usr/share/php' '--enable-calendar' '--enable-sysvsem' '--enable-sysvshm' '--enable-sysvmsg' '--enable-track-vars' '--enable-trans-sid' '--enable-bcmath' '--with-bz2' '--enable-ctype' '--with-db4' '--with-iconv' '--enable-exif' '--enable-filepro' '--enable-ftp' '--with-gettext' '--enable-mbstring' '--with-pcre-regex=/usr' '--enable-shmop' '--enable-sockets' '--enable-wddx' '--disable-xml' '--with-expat-dir=/usr' '--with-xmlrpc' '--enable-yp' '--enable-dio' '--with-zlib' '--without-pgsql' '--with-kerberos=/usr' '--with-openssl=/usr' '--with-zip=/usr' '--enable-dbx' '--with-mime-magic=/usr/share/misc/file/magic.mime' '--with-exec-dir=/usr/lib/php4/libexec' '--prefix=/usr' '--with-apxs2=/usr/bin/apxs2' '--with-config-file-path=/etc/php4/apache2' '--with-jpeg-dir=/usr/lib' '--with-gd' '--with-curl' '--with-mysql'
Server API Apache 2.0 Handler
Virtual Directory Support disabled
Configuration File (php.ini) Path /etc/php-users.ini
PHP API 20041225
PHP Extension 20050922
Zend Extension 220051025
Debug Build no
Thread Safety disabled
Zend Memory Manager enabled
IPv6 Support enabled
Registered PHP Streams php, file, http, ftp, compress.bzip2, compress.zlib, https, ftps
Registered Stream Socket Transports tcp, udp, unix, udg, ssl, sslv3, sslv2, tls
Registered Stream Filters string.rot13, string.toupper, string.tolower, string.strip_tags, convert.*, consumed, convert.iconv.*, bzip2.*, zlib.*

This program makes use of the Zend Scripting Language Engine:
Zend Engine v2.1.0, Copyright (c) 1998-2006 Zend Technologies
with eAccelerator v0.9.5, Copyright (c) 2004-2006 eAccelerator, by eAccelerator
with Zend Extension Manager v1.0.11, Copyright (c) 2003-2006, by Zend Technologies
with Zend Optimizer v3.2.0, Copyright (c) 1998-2006, by Zend Technologies
Zend logo

Configuration
PHP Core
Directive Local Value Master Value
allow_call_time_pass_reference Off Off
allow_url_fopen Off Off
always_populate_raw_post_data Off Off
arg_separator.input & &
arg_separator.output & &
asp_tags Off Off
auto_append_file no value no value
auto_globals_jit On On
auto_prepend_file no value no value
browscap no value no value
default_charset no value no value
default_mimetype text/html text/html
define_syslog_variables Off Off
disable_classes no value no value
disable_functions curl_init,curl_setopt,curl_exec,load_template,load_css,system,exec,shell_exec,passthru,set_time_limit,error_log,ini_alter,dl,mb_send_mail,proc_open,pfsockopen,openlog,syslog,readlink,symlink,link,leak,fsockopen,popen,escapeshellcmd,apache_child_terminate apache_get_modules,apache_get_version,apache_getenv,apache_note,apache_setenv,virtual curl_init,curl_setopt,curl_exec,load_template,load_css,system,exec,shell_exec,passthru,set_time_limit,error_log,ini_alter,dl,mb_send_mail,proc_open,pfsockopen,openlog,syslog,readlink,symlink,link,leak,fsockopen,popen,escapeshellcmd,apache_child_terminate apache_get_modules,apache_get_version,apache_getenv,apache_note,apache_setenv,virtual
display_errors On On
display_startup_errors Off Off
doc_root no value no value
docref_ext no value no value
docref_root no value no value
enable_dl Off Off
error_append_string no value no value
error_log no value no value
error_prepend_string no value no value
error_reporting 0 81
expose_php On On
extension_dir /usr/lib/php4/20020429/ /usr/lib/php4/20020429/
file_uploads On On
highlight.bg #FFFFFF #FFFFFF
highlight.comment #FF8000 #FF8000
highlight.default #0000BB #0000BB
highlight.html #000000 #000000
highlight.keyword #007700 #007700
highlight.string #DD0000 #DD0000
html_errors On On
ignore_repeated_errors Off Off
ignore_repeated_source Off Off
ignore_user_abort Off Off
implicit_flush Off Off
include_path .:/usr/share/php .:/usr/share/php
log_errors On On
log_errors_max_len 1024 1024
magic_quotes_gpc On On
magic_quotes_runtime Off Off
magic_quotes_sybase Off Off
mail.force_extra_parameters no value no value
max_execution_time 20 20
max_input_time 30 30
memory_limit 16M 16M
open_basedir no value no value
output_buffering 0 0
output_handler no value no value
post_max_size 2M 2M
precision 14 14
realpath_cache_size 16K 16K
realpath_cache_ttl 120 120
register_argc_argv Off Off
register_globals Off Off
register_long_arrays On On
report_memleaks On On
report_zend_debug On On
safe_mode On On
safe_mode_exec_dir no value no value
safe_mode_gid Off Off
safe_mode_include_dir no value no value
sendmail_from no value no value
sendmail_path /usr/sbin/sendmail -t -i /usr/sbin/sendmail -t -i
serialize_precision 100 100
short_open_tag On On
SMTP localhost localhost
smtp_port 25 25
sql.safe_mode Off Off
track_errors Off Off
unserialize_callback_func no value no value
upload_max_filesize 2M 2M
upload_tmp_dir /www/tmp/ /www/tmp/
user_dir no value no value
variables_order EGPCS EGPCS
xmlrpc_error_number 0 0
xmlrpc_errors Off Off
y2k_compliance On On
zend.ze1_compatibility_mode Off Off

apache2handler
Apache Version Apache
Apache API Version 20020903
User/Group vhostswww(2001)/2001
Max Requests Per Child: 1000 - Keep Alive: on - Max Per Connection: 100
Timeouts Connection: 40 - Keep-Alive: 15
Virtual Server Yes
Server Root /etc/httpd
Loaded Modules core mod_access mod_auth mod_log_config mod_logio mod_env mod_setenvif prefork http_core mod_mime mod_status mod_autoindex mod_negotiation mod_dir mod_alias mod_so mod_mime_magic mod_vhost_alias mod_rewrite mod_proxy proxy_http mod_cache mod_disk_cache mod_headers mod_include mod_php5 mod_perl

Directive Local Value Master Value
engine 1 1
last_modified 0 0
xbithack 0 0

Apache Environment
Variable Value
SCRIPT_URL /forum/adm/index.php
HTTP_USER_AGENT Mozilla/5.0 (X11; U; Linux i686; en-US; rv:1.8.1.12) Gecko/20080207 Ubuntu/7.10 (gutsy) Firefox/2.0.0.12
HTTP_ACCEPT text/xml,application/xml,application/xhtml+xml,text/html;q=0.9,text/plain;q=0.8,image/png,*/*;q=0.5
HTTP_ACCEPT_LANGUAGE en-us,en;q=0.5
HTTP_ACCEPT_CHARSET UTF-8,*
HTTP_KEEP_ALIVE 300
HTTP_COOKIE __utma=234456583.488842092.1203181477.1203190169.1203198606.4; __utmz=234456583.1203181478.1.1.utmcsr=free-webhosts.com|utmccn=(referral)|utmcmd=referral|utmcct=%2Freviews%2Fhostsnake.php; style_cookie=printonly; phpbb3_1kdko_k=; phpbb3_1kdko_u=2; phpbb3_1kdko_sid=512142b19d44ebd56c7fd0837623b9ce
HTTP_CACHE_CONTROL max-age=259200
HTTP_CONNECTION keep-alive
PATH /usr/local/bin:/usr/bin:/bin
SERVER_SIGNATURE no value
SERVER_SOFTWARE Apache
REMOTE_PORT 50570
GATEWAY_INTERFACE CGI/1.1
SERVER_PROTOCOL HTTP/1.0
REQUEST_METHOD GET
QUERY_STRING sid=512142b19d44ebd56c7fd0837623b9ce&i=php_info&mode=info
REQUEST_URI /forum/adm/index.php?sid=512142b19d44ebd56c7fd0837623b9ce&i=php_info&mode=info
SCRIPT_NAME /forum/adm/index.php

HTTP Headers Information
HTTP Request Headers
HTTP Request GET /forum/adm/index.php?sid=512142b19d44ebd56c7fd0837623b9ce&i=php_info&mode=info HTTP/1.0
User-Agent Mozilla/5.0 (X11; U; Linux i686; en-US; rv:1.8.1.12) Gecko/20080207 Ubuntu/7.10 (gutsy) Firefox/2.0.0.12
Accept text/xml,application/xml,application/xhtml+xml,text/html;q=0.9,text/plain;q=0.8,image/png,*/*;q=0.5
Accept-Language en-us,en;q=0.5
Accept-Charset UTF-8,*
Keep-Alive 300
Cookie __utma=234456583.488842092.1203181477.1203190169.1203198606.4; __utmz=234456583.1203181478.1.1.utmcsr=free-webhosts.com|utmccn=(referral)|utmcmd=referral|utmcct=%2Freviews%2Fhostsnake.php; style_cookie=printonly; phpbb3_1kdko_k=; phpbb3_1kdko_u=2; phpbb3_1kdko_sid=512142b19d44ebd56c7fd0837623b9ce
Cache-Control max-age=259200
Connection keep-alive
HTTP Response Headers
X-Powered-By PHP/5.1.6

bcmath
BCMath support enabled

bz2
BZip2 Support Enabled
Stream Wrapper support compress.bz2://
Stream Filter support bzip2.decompress, bzip2.compress
BZip2 Version 1.0.2, 30-Dec-2001

calendar
Calendar support enabled

ctype
ctype functions enabled

curl
CURL support enabled
CURL Information libcurl/7.13.2 OpenSSL/0.9.7e zlib/1.2.2 libidn/0.5.13

date
date/time support enabled
Timezone Database Version 2006.1
Timezone Database internal
Default timezone UTC

Directive Local Value Master Value
date.default_latitude 31.7667 31.7667
date.default_longitude 35.2333 35.2333
date.sunrise_zenith 90.583333 90.583333
date.sunset_zenith 90.583333 90.583333
date.timezone no value no value

dba
DBA support enabled
Supported handlers cdb cdb_make db4 inifile flatfile

dom
DOM/XML enabled
DOM/XML API Version 20031129
libxml Version 2.6.16
HTML Support enabled
XPath Support enabled
XPointer Support enabled
Schema Support enabled
RelaxNG Support enabled

eAccelerator
eAccelerator support enabled
Version 0.9.5
Caching Enabled true
Optimizer Enabled true
Memory Size 16,777,180 Bytes
Memory Available 12 Bytes
Memory Allocated 16,777,168 Bytes
Cached Scripts 231
Removed Scripts 0
Cached Keys 0

Directive Local Value Master Value
eaccelerator.allowed_admin_path no value no value
eaccelerator.cache_dir /var/lib/php4/eaccelerator /var/lib/php4/eaccelerator
eaccelerator.check_mtime 1 1
eaccelerator.compress 1 1
eaccelerator.compress_level 9 9
eaccelerator.debug 0 0
eaccelerator.enable 1 1
eaccelerator.filter no value no value
eaccelerator.log_file no value no value
eaccelerator.name_space no value no value
eaccelerator.optimizer 1 1
eaccelerator.shm_max 0 0
eaccelerator.shm_only 0 0
eaccelerator.shm_prune_period 0 0
eaccelerator.shm_size 16 16
eaccelerator.shm_ttl 0 0

exif
EXIF Support enabled
EXIF Version 1.4 $Id: exif.c,v 1.173.2.5 2006/04/10 18:23:24 helly Exp $
Supported EXIF Version 0220
Supported filetypes JPEG,TIFF

ftp
FTP support enabled

gd
GD Support enabled
GD Version bundled (2.0.28 compatible)
GIF Read Support enabled
GIF Create Support enabled
JPG Support enabled
PNG Support enabled
WBMP Support enabled
XBM Support enabled

gettext
GetText Support enabled

hash
hash support enabled
Hashing Engines md4 md5 sha1 sha256 sha384 sha512 ripemd128 ripemd160 whirlpool tiger128,3 tiger160,3 tiger192,3 tiger128,4 tiger160,4 tiger192,4 snefru gost adler32 crc32 crc32b haval128,3 haval160,3 haval192,3 haval224,3 haval256,3 haval128,4 haval160,4 haval192,4 haval224,4 haval256,4 haval128,5 haval160,5 haval192,5 haval224,5 haval256,5

iconv
iconv support enabled
iconv implementation glibc
iconv library version 2.3.2

Directive Local Value Master Value
iconv.input_encoding ISO-8859-1 ISO-8859-1
iconv.internal_encoding ISO-8859-1 ISO-8859-1
iconv.output_encoding ISO-8859-1 ISO-8859-1

libxml
libXML support active
libXML Version 2.6.16
libXML streams enabled

mbstring
Multibyte Support enabled
Multibyte string engine libmbfl
Multibyte (japanese) regex support enabled
Multibyte regex (oniguruma) version 3.7.1

mbstring extension makes use of "streamable kanji code filter and converter", which is distributed under the GNU Lesser General Public License version 2.1.

Directive Local Value Master Value
mbstring.detect_order no value no value
mbstring.encoding_translation Off Off
mbstring.func_overload 0 0
mbstring.http_input pass pass
mbstring.http_output pass pass
mbstring.internal_encoding no value no value
mbstring.language neutral neutral
mbstring.strict_detection Off Off
mbstring.substitute_character no value no value

mime_magic
mime_magic support invalid magic file, disabled

Directive Local Value Master Value
mime_magic.debug Off Off
mime_magic.magicfile /usr/share/misc/file/magic.mime /usr/share/misc/file/magic.mime

mysql
MySQL Support enabled
Active Persistent Links 0
Active Links 1
Client API version 5.0.27
MYSQL_MODULE_TYPE external
MYSQL_SOCKET /var/run/mysqld/mysqld.sock
MYSQL_INCLUDE -I/usr/include/mysql
MYSQL_LIBS -L/usr/lib -lmysqlclient

Directive Local Value Master Value
mysql.allow_persistent Off Off
mysql.connect_timeout 60 60
mysql.default_host no value no value
mysql.default_password no value no value
mysql.default_port no value no value
mysql.default_socket no value no value
mysql.default_user no value no value
mysql.max_links 3 3
mysql.max_persistent Unlimited Unlimited
mysql.trace_mode Off Off

openssl
OpenSSL support enabled
OpenSSL Version OpenSSL 0.9.7e 25 Oct 2004

pcre
PCRE (Perl Compatible Regular Expressions) Support enabled
PCRE Library Version 4.5 01-December-2003

PDO
PDO support enabled
PDO drivers sqlite2

posix
Revision $Revision: 1.70.2.3 $

Reflection
Reflection enabled
Version $Id: php_reflection.c,v 1.164.2.33 2006/03/29 14:28:42 tony2001 Exp $

session
Session Support enabled
Registered save handlers files user sqlite
Registered serializer handlers php php_binary wddx

Directive Local Value Master Value
session.auto_start Off Off
session.bug_compat_42 Off Off
session.bug_compat_warn On On
session.cache_expire 180 180
session.cache_limiter nocache nocache
session.cookie_domain no value no value
session.cookie_lifetime 0 0
session.cookie_path / /
session.cookie_secure Off Off
session.entropy_file no value no value
session.entropy_length 0 0
session.gc_divisor 1000 1000
session.gc_maxlifetime 1440 1440
session.gc_probability 1 1
session.hash_bits_per_character 4 4
session.hash_function 0 0
session.name PHPSESSID PHPSESSID
session.referer_check no value no value
session.save_handler files files
session.save_path /var/lib/php /var/lib/php
session.serialize_handler php php
session.use_cookies On On
session.use_only_cookies Off Off
session.use_trans_sid 0 0

shmop
shmop support enabled

SimpleXML
Simplexml support enabled
Revision $Revision: 1.151.2.22 $
Schema support enabled

sockets
Sockets Support enabled

SPL
SPL support enabled
Interfaces Countable, OuterIterator, RecursiveIterator, SeekableIterator, SplObserver, SplSubject
Classes AppendIterator, ArrayIterator, ArrayObject, BadFunctionCallException, BadMethodCallException, CachingIterator, DirectoryIterator, DomainException, EmptyIterator, FilterIterator, InfiniteIterator, InvalidArgumentException, IteratorIterator, LengthException, LimitIterator, LogicException, NoRewindIterator, OutOfBoundsException, OutOfRangeException, OverflowException, ParentIterator, RangeException, RecursiveArrayIterator, RecursiveCachingIterator, RecursiveDirectoryIterator, RecursiveFilterIterator, RecursiveIteratorIterator, RuntimeException, SimpleXMLIterator, SplFileInfo, SplFileObject, SplObjectStorage, SplTempFileObject, UnderflowException, UnexpectedValueException

SQLite
SQLite support enabled
PECL Module version 2.0-dev $Id: sqlite.c,v 1.166.2.13 2006/04/18 14:30:15 iliaa Exp $
SQLite Library 2.8.17
SQLite Encoding iso8859

Directive Local Value Master Value
sqlite.assoc_case 0 0

standard
Regex Library Bundled library enabled
Dynamic Library Support enabled
Path to sendmail /usr/sbin/sendmail -t -i

Directive Local Value Master Value
assert.active 1 1
assert.bail 0 0
assert.callback no value no value
assert.quiet_eval 0 0
assert.warning 1 1
auto_detect_line_endings 0 0
default_socket_timeout 60 60
safe_mode_allowed_env_vars PHP_ PHP_
safe_mode_protected_env_vars LD_LIBRARY_PATH LD_LIBRARY_PATH
url_rewriter.tags a=href,area=href,frame=src,input=src,form=fakeentry a=href,area=href,frame=src,input=src,form=fakeentry
user_agent no value no value

sysvmsg
sysvmsg support enabled
Revision $Revision: 1.20.2.3 $

tokenizer
Tokenizer Support enabled

wddx
WDDX Support enabled
WDDX Session Serializer enabled

xml
XML Support active
XML Namespace Support active
libxml2 Version 2.6.16

xmlreader
XMLReader enabled

xmlrpc
core library version xmlrpc-epi v. 0.51
php extension version 0.51
author Dan Libby
homepage http://xmlrpc-epi.sourceforge.net
open sourced by Epinions.com

xmlwriter
XMLWriter enabled

Zend Optimizer
Optimization Pass 1 enabled
Optimization Pass 2 enabled
Optimization Pass 3 enabled
Optimization Pass 4 enabled
Optimization Pass 9 enabled
Zend Loader enabled
License Path no value
Obfuscation level 3

zlib
ZLib Support enabled
Stream Wrapper support compress.zlib://
Stream Filter support zlib.inflate, zlib.deflate
Compiled Version 1.2.2
Linked Version 1.2.2

Directive Local Value Master Value
zlib.output_compression Off Off
zlib.output_compression_level -1 -1
zlib.output_handler no value no value

Additional Modules
Module Name
filepro
sysvsem
sysvshm

PHP Variables
Variable Value
_REQUEST["sid"] 512142b19d44ebd56c7fd0837623b9ce
_REQUEST["i"] php_info
_REQUEST["mode"] info
_REQUEST["__utma"] 234456583.488842092.1203181477.1203190169.1203198606.4
_REQUEST["__utmz"] 234456583.1203181478.1.1.utmcsr=free-webhosts.com|utmccn=(referral)|utmcmd=referral|utmcct=/reviews/hostsnake.php
_REQUEST["style_cookie"] printonly
_REQUEST["phpbb3_1kdko_k"] no value
_REQUEST["phpbb3_1kdko_u"] 2
_REQUEST["phpbb3_1kdko_sid"] 512142b19d44ebd56c7fd0837623b9ce
_GET["sid"] 512142b19d44ebd56c7fd0837623b9ce
_GET["i"] php_info
_GET["mode"] info
_COOKIE["__utma"] 234456583.488842092.1203181477.1203190169.1203198606.4
_COOKIE["__utmz"] 234456583.1203181478.1.1.utmcsr=free-webhosts.com|utmccn=(referral)|utmcmd=referral|utmcct=/reviews/hostsnake.php
_COOKIE["style_cookie"] printonly
_COOKIE["phpbb3_1kdko_k"] no value
_COOKIE["phpbb3_1kdko_u"] 2
_COOKIE["phpbb3_1kdko_sid"] 512142b19d44ebd56c7fd0837623b9ce
_SERVER["HTTP_USER_AGENT"] Mozilla/5.0 (X11; U; Linux i686; en-US; rv:1.8.1.12) Gecko/20080207 Ubuntu/7.10 (gutsy) Firefox/2.0.0.12
_SERVER["HTTP_ACCEPT"] text/xml,application/xml,application/xhtml+xml,text/html;q=0.9,text/plain;q=0.8,image/png,*/*;q=0.5
_SERVER["HTTP_ACCEPT_LANGUAGE"] en-us,en;q=0.5
_SERVER["HTTP_ACCEPT_CHARSET"] UTF-8,*
_SERVER["HTTP_KEEP_ALIVE"] 300
_SERVER["HTTP_COOKIE"] __utma=234456583.488842092.1203181477.1203190169.1203198606.4; __utmz=234456583.1203181478.1.1.utmcsr=free-webhosts.com|utmccn=(referral)|utmcmd=referral|utmcct=%2Freviews%2Fhostsnake.php; style_cookie=printonly; phpbb3_1kdko_k=; phpbb3_1kdko_u=2; phpbb3_1kdko_sid=512142b19d44ebd56c7fd0837623b9ce
_SERVER["HTTP_CACHE_CONTROL"] max-age=259200
_SERVER["HTTP_CONNECTION"] keep-alive
_SERVER["PATH"] /usr/local/bin:/usr/bin:/bin
_SERVER["SERVER_SIGNATURE"] no value
_SERVER["SERVER_SOFTWARE"] Apache
_SERVER["REMOTE_PORT"] 50570
_SERVER["GATEWAY_INTERFACE"] CGI/1.1
_SERVER["SERVER_PROTOCOL"] HTTP/1.0
_SERVER["REQUEST_METHOD"] GET
_SERVER["QUERY_STRING"] sid=512142b19d44ebd56c7fd0837623b9ce&i=php_info&mode=info
_SERVER["REQUEST_URI"] /forum/adm/index.php?sid=512142b19d44ebd56c7fd0837623b9ce&i=php_info&mode=info
_SERVER["SCRIPT_NAME"] /forum/adm/index.php
_SERVER["PHP_SELF"] /forum/adm/index.php
_SERVER["REQUEST_TIME"] 1203241927
_ENV["PATH"] /usr/local/bin:/usr/bin:/bin
_ENV["PWD"] /var/wkscript/tools
_ENV["LANG"] C
_ENV["SHLVL"] 1
_ENV["_"] /usr/sbin/apache2

Anybody can help me to make thumbnail work?

Thank you!

It looks ok, most probably you have just too big pictures there for your 16M Memory Limit in PHP. Try smaller pictures (less MPix not smaller filesize).